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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-10 15:00:03 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-10 15:00:03 -0800
commitb44a3d2a85c64208a57362a1728efb58a6556cd6 (patch)
tree293302b3ac918eb75b442fa035eb976850163b1d /drivers/cpufreq
parent56e0464980febfa50432a070261579415c72664e (diff)
parentd13a5c8c4c3dbe299659bcff805f79a2c83e2bbc (diff)
downloadlwn-b44a3d2a85c64208a57362a1728efb58a6556cd6.tar.gz
lwn-b44a3d2a85c64208a57362a1728efb58a6556cd6.zip
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Olof Johansson: "As we've enabled multiplatform kernels on ARM, and greatly done away with the contents under arch/arm/mach-*, there's still need for SoC-related drivers to go somewhere. Many of them go in through other driver trees, but we still have drivers/soc to hold some of the "doesn't fit anywhere" lowlevel code that might be shared between ARM and ARM64 (or just in general makes sense to not have under the architecture directory). This branch contains mostly such code: - Drivers for qualcomm SoCs for SMEM, SMD and SMD-RPM, used to communicate with power management blocks on these SoCs for use by clock, regulator and bus frequency drivers. - Allwinner Reduced Serial Bus driver, again used to communicate with PMICs. - Drivers for ARM's SCPI (System Control Processor). Not to be confused with PSCI (Power State Coordination Interface). SCPI is used to communicate with the assistant embedded cores doing power management, and we have yet to see how many of them will implement this for their hardware vs abstracting in other ways (or not at all like in the past). - To make confusion between SCPI and PSCI more likely, this release also includes an update of PSCI to interface version 1.0. - Rockchip support for power domains. - A driver to talk to the firmware on Raspberry Pi" * tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (57 commits) soc: qcom: smd-rpm: Correct size of outgoing message bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus bus: sunxi-rsb: Add Allwinner Reduced Serial Bus (RSB) controller bindings ARM: bcm2835: add mutual inclusion protection drivers: psci: make PSCI 1.0 functions initialization version dependent dt-bindings: Correct paths in Rockchip power domains binding document soc: rockchip: power-domain: don't try to print the clock name in error case soc: qcom/smem: add HWSPINLOCK dependency clk: berlin: add cpuclk ARM: berlin: dts: add CLKID_CPU for BG2Q ARM: bcm2835: Add the Raspberry Pi firmware driver soc: qcom: smem: Move RPM message ram out of smem DT node soc: qcom: smd-rpm: Correct the active vs sleep state flagging soc: qcom: smd: delete unneeded of_node_put firmware: qcom-scm: build for correct architecture level soc: qcom: smd: Correct SMEM items for upper channels qcom-scm: add missing prototype for qcom_scm_is_available() qcom-scm: fix endianess issue in __qcom_scm_is_call_available soc: qcom: smd: Reject send of too big packets soc: qcom: smd: Handle big endian CPUs ...
Diffstat (limited to 'drivers/cpufreq')
-rw-r--r--drivers/cpufreq/Kconfig.arm10
-rw-r--r--drivers/cpufreq/Makefile1
-rw-r--r--drivers/cpufreq/scpi-cpufreq.c124
3 files changed, 135 insertions, 0 deletions
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index 642fd49793b0..1582c1c016b0 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -199,6 +199,16 @@ config ARM_SA1100_CPUFREQ
config ARM_SA1110_CPUFREQ
bool
+config ARM_SCPI_CPUFREQ
+ tristate "SCPI based CPUfreq driver"
+ depends on ARM_BIG_LITTLE_CPUFREQ && ARM_SCPI_PROTOCOL
+ help
+ This adds the CPUfreq driver support for ARM big.LITTLE platforms
+ using SCPI protocol for CPU power management.
+
+ This driver uses SCPI Message Protocol driver to interact with the
+ firmware providing the CPU DVFS functionality.
+
config ARM_SPEAR_CPUFREQ
bool "SPEAr CPUFreq support"
depends on PLAT_SPEAR
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index d11309c487d0..c0af1a1281c8 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -71,6 +71,7 @@ obj-$(CONFIG_ARM_S3C64XX_CPUFREQ) += s3c64xx-cpufreq.o
obj-$(CONFIG_ARM_S5PV210_CPUFREQ) += s5pv210-cpufreq.o
obj-$(CONFIG_ARM_SA1100_CPUFREQ) += sa1100-cpufreq.o
obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o
+obj-$(CONFIG_ARM_SCPI_CPUFREQ) += scpi-cpufreq.o
obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o
obj-$(CONFIG_ARM_TEGRA20_CPUFREQ) += tegra20-cpufreq.o
obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o
diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c
new file mode 100644
index 000000000000..2c3b16fd3a01
--- /dev/null
+++ b/drivers/cpufreq/scpi-cpufreq.c
@@ -0,0 +1,124 @@
+/*
+ * System Control and Power Interface (SCPI) based CPUFreq Interface driver
+ *
+ * It provides necessary ops to arm_big_little cpufreq driver.
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ * Sudeep Holla <sudeep.holla@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/scpi_protocol.h>
+#include <linux/types.h>
+
+#include "arm_big_little.h"
+
+static struct scpi_ops *scpi_ops;
+
+static struct scpi_dvfs_info *scpi_get_dvfs_info(struct device *cpu_dev)
+{
+ u8 domain = topology_physical_package_id(cpu_dev->id);
+
+ if (domain < 0)
+ return ERR_PTR(-EINVAL);
+ return scpi_ops->dvfs_get_info(domain);
+}
+
+static int scpi_opp_table_ops(struct device *cpu_dev, bool remove)
+{
+ int idx, ret = 0;
+ struct scpi_opp *opp;
+ struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev);
+
+ if (IS_ERR(info))
+ return PTR_ERR(info);
+
+ if (!info->opps)
+ return -EIO;
+
+ for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
+ if (remove)
+ dev_pm_opp_remove(cpu_dev, opp->freq);
+ else
+ ret = dev_pm_opp_add(cpu_dev, opp->freq,
+ opp->m_volt * 1000);
+ if (ret) {
+ dev_warn(cpu_dev, "failed to add opp %uHz %umV\n",
+ opp->freq, opp->m_volt);
+ while (idx-- > 0)
+ dev_pm_opp_remove(cpu_dev, (--opp)->freq);
+ return ret;
+ }
+ }
+ return ret;
+}
+
+static int scpi_get_transition_latency(struct device *cpu_dev)
+{
+ struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev);
+
+ if (IS_ERR(info))
+ return PTR_ERR(info);
+ return info->latency;
+}
+
+static int scpi_init_opp_table(struct device *cpu_dev)
+{
+ return scpi_opp_table_ops(cpu_dev, false);
+}
+
+static void scpi_free_opp_table(struct device *cpu_dev)
+{
+ scpi_opp_table_ops(cpu_dev, true);
+}
+
+static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = {
+ .name = "scpi",
+ .get_transition_latency = scpi_get_transition_latency,
+ .init_opp_table = scpi_init_opp_table,
+ .free_opp_table = scpi_free_opp_table,
+};
+
+static int scpi_cpufreq_probe(struct platform_device *pdev)
+{
+ scpi_ops = get_scpi_ops();
+ if (!scpi_ops)
+ return -EIO;
+
+ return bL_cpufreq_register(&scpi_cpufreq_ops);
+}
+
+static int scpi_cpufreq_remove(struct platform_device *pdev)
+{
+ bL_cpufreq_unregister(&scpi_cpufreq_ops);
+ scpi_ops = NULL;
+ return 0;
+}
+
+static struct platform_driver scpi_cpufreq_platdrv = {
+ .driver = {
+ .name = "scpi-cpufreq",
+ .owner = THIS_MODULE,
+ },
+ .probe = scpi_cpufreq_probe,
+ .remove = scpi_cpufreq_remove,
+};
+module_platform_driver(scpi_cpufreq_platdrv);
+
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver");
+MODULE_LICENSE("GPL v2");